A project is proposed to develop and demonstrate the feasibility of an enzyme immunoassay format capable of simultaneously detecting and identifying any one or more of multiple drugs in blood from a finger prick. The eventual goal is to develop a screening test device having a built-in sampler which would allow the user to touch the device onto a drop of blood from a finger prick, turn the device over and tap it to introduce the sample, place the device into a developing solution, wait for a few minutes and observe the results. Any designated bands having color would indicate the presence of the corresponding drug. The specific goal of the proposed Phase I project is to develop the technique, using a simpler apparatus, and to demonstrate that any combination of cocaine, morphine and phencyclidine can be identified in a small blood sample, each at 20 nanograms/ml or greater concentrations.